120 Lake Maxinkitckee, Physical and Biological Survey 



actually gave rise to a musical tinkle, and the water might almost 

 be said to sing and sparkle like champagne. 



Closely associated with supplying oxygen to the water are two 

 or three other functions of considerable importance. The first of 

 these is the softening effect which the plants have upon the water. 

 Certain plants, such as the Charas and the Potamogetons, abstract 

 considerable quantities of lime from the water. These plants be- 

 come thickly covered with a coating of carbonate of lime from 

 which in turn they receive some of their oxygen by reducing the 

 calcium carbonate. These and other plants also modify the bot- 

 tom of the lake by the deposition of the lime as marl and also by 

 the deposition of vegetable debris to form black muck. 



As shade: — Some of the plants, such as the water-lilies with 

 their broad sheltering pads, furnish grateful shade to fishes and 

 other animals of the lake. Any one who has ever rowed silently 

 a.long the edge of a patch of spatterdock on a bright summer day 

 and seen bass and sunfish and other animals resting in the shade 

 of the broad leaves, can not doubt this value of the plants. 



As protection: — The larger aquatic plants offer protection to 

 the fishes in various ways. They protect the fishes from each 

 other. The young of many species habitually dwell among the 

 vegetation until they have attained size and strength to compete 

 with their larger kin ; and even fishes of considerable size find a 

 dense patch of hornwort or Potamogeton quite helpful when pressed 

 by larger fish. The plants also afford protection to the fishes from 

 the watchful eye of kingfishers, herons, fishhawks, and other fish- 

 eating birds. Moreover, many an angler has lost many a good fish 

 because his hook became fouled in the weeds, to the mutual advan- 

 tage of both fish and angler, in that the fish escaped and the angler 

 was given the opportunity to report that "the largest one got 

 away". 



As food: — Many of the plants furnish food to the fishes, either 

 directly or indirectly. So much attention has been given in recent 

 years to plankton and its importance in the menu of young fishes 

 and of the adults of some species such as the shad, white-fish, and 

 shovel-nosed sturgeon, that we are likely to overlook the larger 

 forms of plant life when considering the food of fishes. As a 

 matter of fact, during a large part of the year many of the fishes 

 of the lake obtain a considerable portion of their food from the 

 more conspicuous plants. With the exception of the skipjack, few 

 of the small fishes, after they have passed infancy, feed upon 

 entomostraca. The vegetarian minnows feed upon plants or plant 



